Lethal osteogenesis imperfecta and skin fragility in newborn New Zealand Romney lambs

Abstract

Osteogenesis imperfecta and skin fragility occurred in about 50 New Zealand Romney lambs born in a flock of 450 ewes. Affected lambs had soft bones and multiple intrauterine bone fractures. Long bones had a thickened diaphysis with almost complete absence of a medullary cavity. Other consistent gross findings were moderate brachynathia inferior, subcutaneous oedema, marked joint laxity, dark blue sclera and small pink teeth. Histopathologic and ultrastructural changes were consistent with a defect in collagen production by fibroblasts. DNA finger-printing was used to identify which of the five rams used in the flock was carrying the genetic defect. The disease was inherited as an autosomal dominant trait and was considered to be a new mutation in the testicular germ cell lines of this ram.

Osteogenesis Imperfecta in Two Litters of Dachshunds

“…In that report, an increase in the diaphyseal diameter of long bones in combination with an excessive formation of spongiosa, resulting in a decreased space of the medullary cavity, also was described. 2 The histopathologic changes observed here in these Dachshunds are strongly suggestive of decreased bone formation. A common feature of OI is the normal appearance of growth plates and primary spongiosa, whereas lamellar bone formation is deficient.…”

“…For this reason, dentinogenesis imperfecta has been consistently observed in humans and also has been described in calves and Bedlington Terriers. 1,2,6,13,22,28 Ultrastructural changes were moderate. The cytoplasmic vacuolation of osteoblasts could be the result of an intracytoplasmic accumulation of procollagen caused by a secretion defect, as has been described in humans.…”

“…In sheep, trabeculae have been reported to be increased in number but were found to be very narrow and covered by a thin layer of basophilic bone tissue. 2 The small amount of fibrous tissue with the moderate new bone formation observed in the mandible of dog No. 3 and the periostal new bone formation in dog Nos.…”

“…26,37 OI has been documented previously in cattle, sheep, domestic cats, mice, and tigers. 1,2,10,11,14,16,18,19,21,23,31 In dogs, OI has been reported in Golden Retrievers, Collies, Poodles, Beagles, Norwegian Elkhound, and Bedlington Terriers. 8,17,22,29 Young animals are mostly affected during the first few weeks of life.…”

Dermatosparaxis in two White Doper lambs in Brazil: case report

“…Osteogenesis imperfecta is characterized by long bones with thickened diaphysis and no or small medullary cavity. It is associated with subcutaneous edema and joint laxity, with histopathological and ultrastructural evidences of a defect in collagen production (Arthur et al, 1992). Therefore, osteogenesis imperfecta must be considered in the differential diagnosis of dermatosparaxis (Vaastra et al, 2011).…”